Plasma Levels of Cholecystokinin (CCK-8 and CCK-33-39) in Response to Feeding and during Pregnancy in Dogs

Abstract

A method for measuring plasma cholecystokinin (CCK) levels in dogs which enables separate determination of small (CCK-8) and large (CCK-33-39) molecular forms by using reversed-phase high-performance liquid chromatography before radioimmuno-assay is presented. Basal levels of CCK averaged 1.8 pM and rose to 4.6 pM 60 min after feeding. The ratio between small and large molecular forms was 1:1 in basal samples but 3:1 and 1:2 in samples collected 10 and 60 min after feeding, respectively. In pregnant dogs basal CCK levels were significantly increased (5 pM) and equally distributed for CCK-8 and CCK-33-39.

Key Words:

• Cholecystokinins
• feeding
• peptides in dog plasma
• pregnancy